OBJECTIVETo understand the distribution, fauna, population structure of host animals and their parasitic fleas as well as popular dynamic of animal plague of natural plague foci in Junggar Basin.

METHODSSample materials and data of animals and vector insects were collected using ecological methods and the population structures were analyzed statistically. F1 antibody of Yersinia pestis in rodents' serum and organ suspension was detected by means of IHA while the pathogen of Y. pestis in rodents and vector insects was detected by means of aetiological detections and the isolated Y. pestis was detected using biochemical methods.

RESULTSThe small mammals which were found in Junggar Basin belonged to 17 species of 11 genera 7 families. Of them, 13 species of rodents were included whose parasitic fleas belonged to 19 species of 10 genera 8 families. The average coverage of Rhombomys opimus hole-community was 22.5% in Junggar Basin with the average density of R. opimus hole-community was 15.9/hm2 and the average rate of habitat of the hole-community was 70.2%. In the R. opimus community, the average density of rodents was 3.1/hole-community, and 34.4/hm2 in the nature plague foci. In the population structure of the hole-community of R. opimus, R. opimus accounted for 72.9% in the total captured rodents, Meriones meridianus was 24.5% while the others were 2.6%. In the nocturnal community of rodents, M. meridianus accounted for 64.0% in total captured rodents, Dipus sagitta was 15.1%, M. erythrourns was 7.5% and the others were 13.4%. In the rodents community of Junggar Basin, the rate of R. opimus with fleas was 84.9%, which was the highest, followed by M. tamariscinus, Euchoreutes naso and M. erythrourns, with the rates as 71.4%, 66.7% and 62.7% respectively. The rate of M. meridianus with fleas was 38.3%. There were 16 species of parasitic fleas in R. opimus, with the total flea index as 8.58 and the dominant species was Xenopsylla skrjabini. There were 17 and 16 kinds of fleas in M. erythrourns and M. meridianus respectively with the total flea index were 1.59 and 1.15, with dominant fleas were Nosopsyllus laeviceps and X. skrjabini. The serum and organ suspension of 3179 rodents which belonged to 12 species were detected by means of IHA, of them 174 samples were positive and the positive rate was 5.5%. There were 1356 samples of R. opimus in these materials, and 164 were positive, accounted for 12.1%. The samples of M. meridianus were 1255, with 9 positive, accounted for 0.7%. The samples of D. sagitta were 116 with 1 positive and the rate was 0.9%. The samples of other rodents were 452 but were all negative. There were in total 2975 organs collected from rodents, when detected by methods of isolated of Y. pestis. 15 strains of Y. pestis were isolated from 1243 R. opimus, and 2 strains isolated from 1230 M. meridianus. A total number of 11 647 fleas from rodents were detected by methods of isolated of Y. pestis in which 1 strain of Y. pestis was isolated from 4713 X. skrjabini, and 6 were isolated from 2101 Xenopsylla minax, 1 from 328 Xenopsylla conformis conformis and 1 from 250 Echidnophaga oschanini. Among the other 4255 fleas, none was isolated. The biochemical properties of these Y. pestis which isolated from Junggar Basin were positive of Maltose, Ejiao sugar and Glycerol, and negative of Rhamnose and Nitrogen, which were all strongly poisonous to mouse.

CONCLUSIONThe natural plague foci in Junggar Basin spread all over the whole Junggar Basin. There were animal plague cases found in 12 counties (cites) while Karamy, Bole, Jimusaer and Qitai were confirmed as plague foci counties (cities). Animals and vector insects of the foci were complicated but the ecological system was stable. R. opimus was recognized as the dominant host animal and its biochemical type belonged to the Middle Ages, suggesting that the foci was a new type of natural plague foci.

Animals ; China ; epidemiology ; Gerbillinae ; microbiology ; Mice ; Plague ; epidemiology ; microbiology ; Rodent Diseases ; epidemiology ; microbiology ; Yersinia pestis ; immunology ; pathogenicity

A total of 1,618 ticks [420 individual (adults) and pooled (larvae and nymphs) samples], 369 rodents (Apodemus arius, Rattus norvegicus, Tscherskia triton, Mus musculus, and Myodes regulus), and 34 shrews (Crocidura lasiura) that were collected in northern Gyeonggi-do near the Demilitarized Zone (DMZ) of Korea during 2004-2005, were assayed by PCR for selected zoonotic pathogens. From a total of 420 individual and pooled tick DNA samples, Anaplasma (A.) phagocytophilum (16), A. platys (16), Ehrlichia (E.) chaffeensis (63), Borrelia burgdorferi (16), and Rickettsia spp. (198) were detected using species-specific PCR assays. Out of 403 spleens from rodents and shrews, A. phagocytophilum (20), A. platys (34), E. chaffeensis (127), and Bartonella spp. (24) were detected with species-specific PCR assays. These results suggest that fevers of unknown causes in humans and animals in Korea should be evaluated for infections by these vector-borne microbial pathogens.
Anaplasma phagocytophilum/genetics/isolation & purification ; Animals ; Biological Warfare ; DNA, Bacterial/genetics/isolation & purification ; Ehrlichiosis/transmission/veterinary ; Humans ; Korea ; Mice/*microbiology ; Rats/*microbiology ; Seasons ; Shrews/*microbiology ; Ticks/*microbiology ; Zoonoses

OBJECTIVETo explore the mechanism of fulminate hepatic failure (FHF) complicated with spontaneous peritonitis (SBP) through the research of bacteria invading the intestinal mucosa barrier.

METHODS240 BalB/c male mice were divided into four groups as isotonic NS group (n = 40), lipopolysaccharide (LPS) group (n = 40), galactosamine (GalN) group (n = 40) and FHF model group (n = 120). Each mouse received same volume of NS, LPS (10 ug/kg), GalN (800 mg/kg) or LPS (10 ug/kg)/GalN (800 mg/kg) intraperitoneal injection according to its group. 8 mice were executed at 2, 6, 9, 12 and 24 hours after injection, respectively, and the liver and intestinal tissue samples were taken at the same time. ALT was measured by automatic biochemical analyzer and was compared between groups using Mann-Whitney U test. Liver and intestinal tissue received HE staining. The ultrastructure of intestinal mucosa and the method by which bacteria invaded the intestinal mucosa were observed by transmission electron microscopy. All data were analyzed by SPSS13.0 statistic software.

RESULTSALT level, results of hepatic pathology, mortality and clinical manifestations of mice in the FHF model group met the diagnostic criteria of FHF. Intestinal tissue was found with slight edema and little inflammatory cells infiltration through HE staining in all the 4 groups of mice 9 hours after injection. Microvilli were found broken, shed and shorten in the intestinal epithelial cells with incomplete tight junction (TJs) and obviously changed organelles in the FHF model group of mice observed by transmission electron microscope. Mass hemorrhagic necrosis of liver cells with remnant liver cells swelling and many inflammatory cells infiltration by HE staining in the FHF model group. But the changes in hepatic pathology and intestinal mucosa ultrastructure were not so obvious in the mice of NS, LPS and GalN groups. Bacteria penetrated the intestinal wall by pinocytosis 6 to 9 hours after injection in the FHF model group, the microvilli were broken off and TJs turned rupture in the areas that the bacteria penetrated. The bacteria were found in the form of cyst 12 hours after injection.

CONCLUSIONLPS (10 mg/kg)/GalN (800 mg/kg) combined injection was successful in establishing the FHF mice model. The rupture of TJs may provide conditions for intestinal bacteria to penetrate the intestinal mucosa in FHF. Rupture of TJs may be one of the reasons why FHF was complicated with SBP.

Animals ; Disease Models, Animal ; Intestinal Mucosa ; microbiology ; pathology ; Liver ; pathology ; Liver Failure, Acute ; microbiology ; pathology ; Male ; Mice ; Mice, Inbred BALB C ; Tight Junctions ; microbiology ; pathology

OBJECTIVETo observe whether H. pylori inoculated by oral route could arrive in livers and cause liver inflammation as an independent etiological factor.

METHODSC57BL/6 mice were orally inoculated with H. pylori SS1 strains and fed for 8 months. H. pylori colonization and pathologic consequences were studied in the liver and gallbladder tissues of the mice; the blood, liver tissue and gastric mucosa were obtained and cultured for H. pylori growth; The bacterial DNA extracted from the liver, bile and blood was examined by nested PCR for H. pylori genes. 16S rRNA PCR amplicons were sequenced and compared with the sequencing results of 16S rRNA PCR amplicons of the bacteria cultured from gastric mucosa and the inoculated H. pylori SS1.

RESULTSThe bacterial DNA extracted from the liver, bile and blood of the infected mice was detected for H. pylori genes by nested PCR. Six of the 15 samples were positive (40%) in the liver, 6 of 10 samples in the bile (60%), and 2 of 10 samples in the blood (20%). Sequencing results of 16S rRNA PCR products of the livers showed 100% homogeneity when compared with the cultured H. pylori from gastric mucosa and inoculated H. pylori SS1. H. pylori was found in 4 liver tissues of the 15 infected mice (26.7%) and 6 in the gallbladders (40%). Infiltrations of lymphocyte cells along hepatic sinusoids and a lower degree infiltration around interlobular arteries and veins were observed; ballooning degeneration was also observed in some hepatocytes.

CONCLUSIONH. pylori inoculated by oral route could arrive in the liver and cause inflammation as an independent etiological factor. The routes which the microorganisms took to reach the livers may involve hematogenous and/or biliary system dissemination.

Animals ; Helicobacter Infections ; Helicobacter pylori ; pathogenicity ; Liver ; microbiology ; Male ; Mice ; Mice, Inbred C57BL ; Rats

Ulcerative Colitis (UC) has been reported to be related to Porphyromonas gingivalis (P. gingivalis). Porphyromonas gingivalis peptidylarginine deiminase (PPAD), a virulence factor released by P. gingivalis, is known to induce inflammatory responses. To explore the pathological relationships between PPAD and UC, we used homologous recombination technology to construct a P. gingivalis strain in which the PPAD gene was deleted (Δppad) and a Δppad strain in which the PPAD gene was restored (comΔppad). C57BL/6 mice were orally gavaged with saline, P. gingivalis, Δppad, or comΔppad twice a week for the entire 40 days (days 0-40), and then, UC was induced by dextran sodium sulfate (DSS) solution for 10 days (days 31-40). P. gingivalis and comΔppad exacerbated DDS-induced colitis, which was determined by assessing the parameters of colon length, disease activity index, and histological activity index, but Δppad failed to exacerbate DDS-induced colitis. Flow cytometry and ELISA revealed that compared with Δppad, P. gingivalis, and comΔppad increased T helper 17 (Th17) cell numbers and interleukin (IL)-17 production but decreased regulatory T cells (Tregs) numbers and IL-10 production in the spleens of mice with UC. We also cocultured P. gingivalis, Δppad, or comΔppad with T lymphocytes in vitro and found that P. gingivalis and comΔppad significantly increased Th17 cell numbers and decreased Treg cell numbers. Immunofluorescence staining of colon tissue paraffin sections also confirmed these results. The results suggested that P. gingivalis exacerbated the severity of UC in part via PPAD.
Animals ; Colitis, Ulcerative/microbiology* ; Mice ; Mice, Inbred C57BL ; Porphyromonas gingivalis/pathogenicity* ; Protein-Arginine Deiminases ; Virulence Factors

OBJECTIVEOver the past several decades, there has been a significant increase in allergy and asthma in the world, which correlates with alterations in microflora and widespread use of antibiotics. The authors have developed a mouse model of antibiotics-induced microbiota disruption. In that model, mice were challenged by intranasal exposure to Aspergillus fumigatus allergens to explore the relation of allergic airway response and intestinal microflora disruption.

METHODSSixty female BALB/c mice were divided at random into 6 groups with 10 mice in each. (1) First antibiotic therapy group: the mice were given oral cefoperazone for 7 days, on day 7, mice were inoculated with Candida albicans (10(9)/ml, 50 microl) orally. (2) First control group: the mice were treated as first antibiotic therapy group, but cefoperazone and Candida albicans were replaced by saline. The mice in groups (1) and (2) were sacrificed on day 8, and cecal contents were collected for quantitative analysis of the intestinal bacterial flora. (3) Antibiotic therapy and challenge group: the mice were treated as the first antibiotic therapy group, then challenged (day 9 and 16) by intranasal exposure to Aspergillus fumigatus allergen. (4) Second antibiotic therapy group: the mice were treated as the first antibiotic therapy group, then challenged (day 9 and 16) by intranasal exposure to saline. (5) Challenge group: the mice were treated as the first control group, then challenged (day 9 and 16) by intranasal exposure to Aspergillus fumigatus allergen. (6) Second control group: the mice were treated as the first control group, then challenged (day 9 and 16) by intranasal exposure to saline. The mice in (3) - (6) group were killed for analysis of allergic airway response on day 19.

RESULTSThe quantity of Enterobacteriaceae, Enterococcus, Bifidobacterium and Lactobacillus in first antibiotic therapy group was significantly lower than that in the first control group, the quantity of Candida albicans increased in the first antibiotic therapy group as compared with the first control group. Mice intestinal microflora were disrupted with weight reduction and increased moisture in feces. After challenging with Aspergillus fumigatus allergens via intranasal inhalation, the total cell count, eosinophils, lymphocytes and neutrophils increased in BALF, especially in bronchoalveolar lavage fluid (BALF) from the mice in antibiotic therapy and challenge groups. IL-4 level in BALF from antibiotic therapy and challenge group (45.35 +/- 2.36) pg/ml was higher than that in the second control group (35.32 +/- 2.53) pg/ml. The expression of GATA-3 mRNA in the mice lung tissue (0.569 +/- 0.023) was higher than that in the second control group (0.410 +/- 0.020), and the ratios of T-bet/GATA-3 (0.578 +/- 0.021) decreased as compared with that in the second control group (0.804 +/- 0.035). IFN-gamma level in BALF from any group was not significantly different. In the absence of antibiotics, mice exposed to Aspergillus fumigatus allergen did not develop an allergic response in the airways.

CONCLUSIONSThe allergic (Th2) immune response can be induced by airway challenge with Aspergillus fumigatus allergen in the mice in which the intestinal microflora disruption resulted from antibiotic therapy, this result suggests that the intestinal microflora disruption resulted from antibiotic therapy is a risk factor for allergy and asthma.

Animals ; Anti-Bacterial Agents ; adverse effects ; Antibiosis ; Aspergillus fumigatus ; chemistry ; growth & development ; Asthma ; drug therapy ; microbiology ; Bronchoalveolar Lavage Fluid ; microbiology ; Cefoperazone ; therapeutic use ; Disease Models, Animal ; Eosinophils ; drug effects ; microbiology ; Female ; Hypersensitivity ; drug therapy ; microbiology ; Hypersensitivity, Immediate ; microbiology ; Intestines ; drug effects ; microbiology ; physiopathology ; Lung ; drug effects ; microbiology ; Mice ; Mice, Inbred BALB C ; Ovalbumin ; adverse effects ; immunology ; Respiratory System ; microbiology

TcpC is a homolog of the Toll/interleukin-1 receptor (TIR) domain and is secreted by uropathogenic E. coli strain CFT073. TcpC can bind to MyD88, hereby exerting inhibitory effects on macrophages. TcpC represents an important virulence factor that promotes bacterial survival and pathogenicity. TcpC plays a critical role in urinary tract infection, particularly in the pathogenesis of pyelonephritis. In this review,the progress and prospects in TcpC research are discussed.
Animals ; Escherichia coli ; pathogenicity ; Escherichia coli Proteins ; physiology ; Humans ; Mice ; Pyelonephritis ; microbiology ; Urinary Tract Infections ; microbiology ; Virulence Factors ; physiology

Human gut microbiota plays a key role in the development of obesity. Intestinal flora can regulate energy absorption and nutrition metabolism, increasing the energy harvesting from diet. Alteration of gut flora produces excessive lipopolysaccharide, which, when absorbed into the blood, can induce inflammatory reactions and promote the high-fat diet-associated obesity and metabolic syndrome. Intestinal flora increase visceral fat deposition by lowering the expression of Fiaf in intestinal mucosa. Different immune status also affects the intestinal flora.The gut microbiota is hypothesized to be an environmental factor that contributes to obesity; by interacting with factors such as host and diet, it adjusts the energy metabolism. Antibiotics or probiotics may alter the composition of intestinal microflora and improve the metabolic syndrome, and thus provides new treatment options.
Animals ; Diet, High-Fat ; Gastrointestinal Tract ; microbiology ; Humans ; Inflammation ; etiology ; Mice ; Obesity ; microbiology ; therapy ; Probiotics ; therapeutic use

To grow Mycobacterium leprae in cultured mouse peritoneal macrophages, studies were made on 1) the purification of M. leprae from lepromatous nodules by trypsinization, 2) growth experiment of purified M. leprae in cu1tured macrophages by in vivo infection-in vitro cultivation technique and 3) the observation of pathological changes in sp1eens of mice induced by intraperitoneal inoculation of purified M. leprae. Results are summarized as follows. 1. A simple and effective procedure is described for purification of M. leprae from biopsied nodules of lepromatous leprosy patients by trypsinization and high speed centrifugation. The procedure resulted in a good yie1d of homogeneous preparation of M. leprae with a negligible contamination of tissue debris. 2. Significant decreases were observed in the numbers of acid-fast bacilli in cultured macrophages and of macrophages harboring acid-fast bacilli by the length of intervals between the time of intraperitoneal inoculation of purified M. leprae and the time of initiation of macrophage cultures. 3. Microscopic examination of stained preparations of macrophages cultured by in vivo infection-in vitro cultivation technique indicated that an apparent increase in the number of acid-fast bacilli in the macrophages occurred when the cultures made at 24 hours and 1 week after inoculation were maintained in vitro up to 2 months or more. 4. Pathological changes in the spleens of mice inoculated with purified M. leprae were of mainly degenerative nature in the red pulp. No multiplication of M. leprae was observed in the spleens of mice up to 5 months after inoculation.
Adolescent ; Adult ; Animal ; Cells, Cultured ; Female ; Human ; Leprosy/microbiology* ; Macrophages/microbiology* ; Male ; Mice ; Mycobacterium leprae/growth & development* ; Mycobacterium leprae/isolation & purification ; Peritoneum/microbiology*

OBJECTIVETo investigate the contamination state of Legionella in cooling water samples from different places in Wuxi city and reveal the molecular biological characteristics of Legionella strains.

METHODS112 parallel water samples (500 ml each) were collected from 56 sites in Wuxi city during year 2009 - 2010. The samples were used for Legionella test and quantitative culture. The isolated Legionella strains were used for serotyping, pulsed-field gel electrophoresis (PFGE), sequence-based typing (SBT), and intracellular growth were tested.

RESULTSThe positive proportion of Legionella was 39. 3% (22/56) among all sampling sites. A total of 29 Legionella strains were isolated, and the serotypes include LP1, LP3, LP5 and LP6. LP1 serotype was the major one with a proportion of 65.5% (19/29). 29 Legionella strains got 17 PFGE types. There were 10 SBT types among 10 Legionella strains with different PFGE types. Comparing to LP1 strain (ATCC 33152), WX2011062 (LP6) and WX2011067 (LP5) had strong intracellular growth ability in mouse peritoneal macrophages J774 cell line (the amount of intracellular bacteria on day 0 after infection were (5.5 +/- 1.32) x 10(5), (3.9 +/- 0.60) x 10(5), (7.8 +/- 0.76) x 10(5) CFU/ml, respectively; the amount of intracellular bacteria on day 3 after infection were (58.3 +/- 1.61) x 10(5), (2700.0 +/- 655.74) x 10(5), (3066.7 +/- 208.17) x 10(5) CFU/ml, respectively).

CONCLUSIONThe Legionella contamination existed in cooling water samples from different places in Wuxi city. Legionella strains isolated showed high genetic variation. Some Legionella strains had vigorous intracellular growth ability.

Air Conditioning ; Animals ; Cells, Cultured ; Environmental Microbiology ; Legionella ; genetics ; growth & development ; isolation & purification ; Legionella pneumophila ; growth & development ; isolation & purification ; Macrophages ; microbiology ; Mice ; Serotyping ; Water Microbiology